1. Field of the Invention
This invention relates, in general, to computer systems and, more specifically, to categorized content retrieval for a digital library.
2. Description of the Prior Art
It is a frequent occurrence that computer users must search a digital information system to locate or obtain contents which best meets their interests. An example of a digital information system is the World Wide Web (www) on the Internet. A vast amount of digitally stored data is available on the web for use by online computer users who can effectively locate the desired materials. Several searching techniques and search engines are known in the prior art and are available for use in performing this process, but these have some restrictions which can make it difficult to locate the area, file, or item of interest.
An advantage of real-time electronic content distribution over traditional paper or CD-ROM media distribution is its interactivity. The traditional distribution methods have fixed organizational and categorized data information which cannot be changed once the media is distributed. Therefore, customized searches and customized information retrieval is impossible. Content-based searches can also be unproductive, whether accomplished on a fixed media or in an online session, when the search parameters are too broad or too narrow. If too broad, too many "hits" of irrelevant matter may make the search results difficult to analyze. If too narrow, some highly relevant materials may be left out of the search results. In order for searches to be most productive, the contents thereof should be categorized more effectively so that the user can navigate through the contents easily and intuitively find the desired information, or data.
Many of the categorization functions provided by existing content distribution facilities are based upon predefined information, which is as static and unchangeable as if distributed on a fixed media like CD-ROM. In these cases, changing the categorization requires a large amount of work and usually requires that the distribution of the data be halted during the process. Consequently, it is desirable, and it is an object of this invention, to provide an efficiently categorized content retrieval mechanism which can be changed dynamically without interrupting the dissemination of the data or information.
While most content retrieval systems display the contents in a tree-type structure and allow navigation to more detailed "branches" on the tree, the navigation paths are fixed and are limited to one direction only. This hampers the user in looking at the contents and finding the area or areas of great relevance. In addition, the starting point for the retrieval of information is usually fixed by the retrieval system and cannot be changed by the user to better define the point at which he wishes to enter the search results. Therefore, it is also desirable, and a further object of this invention, to provide a content retrieval mechanism which is two-direction searchable during user navigation and which can permit different starting points for different users.